Chiang Jyh-Min, Iverson Louts R, Prasad Anantha, Brown Kim J
Department of Environmental and Plant Biology, Ohio University, Athens, Ohio 45701, USA.
J Integr Plant Biol. 2008 Nov;50(11):1426-39. doi: 10.1111/j.1744-7909.2008.00749.x.
Forests are dynamic in both structure and species composition, and these dynamics are strongly influenced by climate. However, the net effects of future tree species composition on net primary production (NPP) are not well understood. The objective of this work was to model the potential range shifts of tree species (DISTRIB Model) and predict their impacts on NPP (PnET-II Model) that will be associated with alterations in species composition. We selected four 200 x 200 km areas in Wisconsin, Maine, Arkansas, and the Ohio-West Virginia area, representing focal areas of potential species range shifts. PnET-II model simulations were carried out assuming that all forests achieved steady state, of which the species compositions were predicted by DISTRIB model with no migration limitation. The total NPP under the current climate ranged from 552 to 908 g C/m(2) per year. The effects of potential species redistributions on NPP were moderate (-12% to +8%) compared with the influence of future climatic changes (-60% to +25%). The direction and magnitude of climate change effects on NPP were largely dependent on the degree of warming and water balance. Thus, the magnitude of future climate change can affect the feedback system between the atmosphere and biosphere.
森林在结构和物种组成方面都是动态变化的，而且这些动态变化受到气候的强烈影响。然而，未来树木物种组成对净初级生产力（NPP）的净效应尚未得到充分理解。这项工作的目标是对树木物种的潜在范围变化进行建模（DISTRIB模型），并预测它们对与物种组成变化相关的NPP的影响（PnET-II模型）。我们在威斯康星州、缅因州、阿肯色州以及俄亥俄州 - 西弗吉尼亚州地区选择了四个200×200公里的区域，这些区域代表了潜在物种范围变化的重点区域。PnET-II模型模拟是在假设所有森林达到稳态的情况下进行的，其中物种组成由无迁移限制的DISTRIB模型预测。当前气候条件下的总NPP范围为每年552至908克碳/平方米。与未来气候变化的影响（-60%至+25%）相比，潜在物种重新分布对NPP的影响较为温和（-12%至+8%）。气候变化对NPP的影响方向和程度在很大程度上取决于变暖程度和水平衡。因此，未来气候变化的幅度会影响大气和生物圈之间的反馈系统。
